Disc cartridge

Abstract

A disc cartridge capable of effectively preventing a recording surface section of a disc from being directly contacted by an inner surface of a casing. The disc cartridge includes a casing having a space defined therein. An inner surface of the casing has a rear end surface section which is positioned opposite to an insertion side of the disc cartridge and against which a peripheral portion of the disc is abutted. The rear end surface section is formed into a substantially sideways V-shape so that the disc may be positioned at substantially a center of the casing in a width direction of the casing along the rear end surface section.

What is claimed is: 
     
       1. A disc cartridge comprising: a casing comprising an upper cover plate and a lower cover plate joined together to define a space therebetween; and   a disc rotatably housed in said space of said casing;   said casing having an inner surface which has a peripheral surface section which is opposite to an insertion side of said disc cartridge and against which said disc abuts, at least a part of said peripheral surface section comprising a slanting surface shape section formed so as to slant toward a center of said peripheral surface section in a width direction thereof between said cover plates wherein said slanting surface shape section has a lubricating disc holding member applied thereto.   
     
     
       2. A disc cartridge as defined in claim 1, said slanting surface shape section comprises a substantially V-shaped rear end surface section. 
     
     
       3. The cartridge of claim 2, wherein an apex of said substantially V-shaped rear end surface section is positioned at substantially the center of said peripheral surface section in the width direction thereof, so that the disc may be guided and positioned at a center of said casing in the width direction thereof, without generating unsteadiness of the disc. 
     
     
       4. A disc cartridge as defined in claim 1, wherein said disc holding member is formed of a material selected from the group consisting of ultra-high-molecular-weight polyethylene, ultra-high-molecular-weight polyethylene foam, graphite teflon polyester (PET), and a metal material exhibiting low friction and wear resistance. 
     
     
       5. A disc cartridge as defined in claim 4, wherein said disc holding member is formed into a sheet-like shape. 
     
     
       6. A disc cartridge as defined in claim 5, wherein said disc holding member is applied to at least a portion of each of an upper inner surface section and a lower inner surface section adjacent to said slanting surface shape section. 
     
     
       7. The cartridge of claim 1, wherein said peripheral surface section is curved over a direction substantially perpendicular to said width direction. 
     
     
       8. The cartridge of claim 1, wherein said slanting surface shape section is formed and positioned to guide said disc and position the same at a center of said casing in the width direction, without generating unsteadiness of the disc. 
     
     
       9. The cartridge of claim 1, wherein said peripheral surface section extends between said cover plates over said width direction thereof. 
     
     
       10. The cartridge of claim 1, wherein said cover plates are fixedly joined to one another, to retain said disc in said space at all times.